Leprechaun Science | Magic Milk for St. Patrick’s Day

The tricky leprechauns are at it again! This time they’ve used their powers to produce St. Patrick’s Day science experiment magic. Using just three ingredients found in your kitchen, you, too, can perform magic leprechaun science that will delight and dazzle the kids this St. Patrick’s Day. If you love this activity be sure to check out our collection of 17 St. Patrick’s Day science activities for kids!

This St. Patrick’s day science experiment is frequently called magic milk or marbled milk. It is one of our family favorites because it a little bit art, a little bit science, and always a ton of fun for kids of all ages. We love to customize the colors and shapes for each holiday or season. (Check out our Valentine’s Day Magic Milk or our Holiday Magic Milk for examples!)

Shamrock Science

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We gathered the following kitchen supplies to perform our St. Patrick’s Day science magic:

• Milk (we used whole milk, but anything from skim to full cream will work)
• Shamrock Cookie Cutter
• Green Food Coloring
• Liquid Dish Soap

We have done the magic milk experiment several times so my kids knew right what to do.

First we poured some milk into a flat dish. We placed the shamrock cookie cutter into the milk.

The kids dripped a couple of drops of food coloring into the center of the cookie cutter and then carefully dripped on drop of liquid dish soap into the center of the food coloring.

They always take a few minutes to admire the swirling colors trapped in the cookie cutter.

To cap off the experiment, it’s really fun to pick up the cookie cutter and watch as the food coloring explodes throughout the dish!

Repeat this St. Patrick’s Day science experiment over and over again by rinsing out the dish and repeating these steps!

St. Patrick’s Day Science Experiment

Why do the colors explode when dish soap is added to the milk?

Put simply, the dish soap interrupts the molecules at the surface of the milk, making them spread out. This makes the colors spread out, leaving a beautiful marbled pattern behind. You can read my full explanation here if you are interested. The science behind what you see in magic milk is pretty fascinating!

Looking for more St. Patrick’s Day science for kids? Steve Spangler has an amazing Leprechaun Science Kit that includes materials for tricks such as uncovering hidden rainbows, experiencing the magic of color-changing Leprechaun beads, fishing for Leprechauns with appearing green worms, and much, much more! The kit comes with all the materials you need, easy step-by-step instructions, and an explanation of the science behind what you see. Click on the image below to find out more!